Bluetooth DUN modem

[Johnny Who]

I have a mobile phone (Samsung GT-S3650) which is claimed to be able to function as DUN modem with an app samsung should have provided. I can pair it to my system, and I have also configured it to work as a DUN modem through Gnome System Settings but it doesnt work. How could I do that? Notice that the phone is not on Android, it is only java enabled.